iGCSE Biology Section 2 lesson 1

1. iGCSE Biology Section 2 lesson 1

2. Content The iGCSE Biology course Section 1: The nature and variety of living organisms Section 2: Structures and functions in living organisms Section 3: Reproduction and inheritance Section 4: Ecology and the environment Section 5: Use of biological resources

3. Content The iGCSE Biology course Section 1: The nature and variety of living organisms Section 2: Structures and functions in living organisms Section 3: Reproduction and inheritance Section 4: Ecology and the environment Section 5: Use of biological resources

4. Content Section 2 Structures and functions in living organisms a) Levels of organisation b) Cell structure c) Biological molecules d) Movement of substances into and out of cells e) Nutrition f) Respiration g) Gas exchange h) Transport i) Excretion j) Coordination and response

5. Content Section 2 Structures and functions in living organisms a) Levels of organisation b) Cell structure c) Biological molecules d) Movement of substances into and out of cells e) Nutrition f) Respiration g) Gas exchange h) Transport i) Excretion j) Coordination and response

6. Content Lesson 1 a) Levels of organisation 2.1 describe the levels of organisation within organisms: organelles, cells, tissues, organs and systems.

7. Content Lesson 1 b) Cell structure 2.2 describe cell structures, including the nucleus, cytoplasm, cell membrane, cell wall, chloroplast and vacuole 2.3 describe the functions of the nucleus, cytoplasm, cell membrane, cell wall, chloroplast and vacuole 2.4 compare the structures of plant and animal cells.

8. Levels of Organisation

9. Levels of Organisation A. Cells

10. Levels of Organisation A. Cells

11. Levels of Organisation A. Cells

12. Levels of Organisation A. Cells

13. Levels of Organisation A. Cells

14. Levels of Organisation A. Cells

15. Levels of Organisation A. Cells

16. Levels of Organisation A. Cells

17. Levels of Organisation A. Cells

18. Levels of Organisation A. Cells

19. Levels of Organisation A. Cells

20. Comparing plant and animal cells

21. Comparing plant and animal cells

22. Comparing plant and animal cells

23. Specialised cells

24. Specialised cells

25. Specialised cells

26. Specialised cells

27. Levels of Organisation B Tissues Tissues are groups of similar cells that are able to work together to carry out a specific function.

28. Levels of Organisation B Tissues eg. Muscle tissue Muscle tissue is very specialised, and has the ability to contract and also to conduct electrical impulses. There are three types of muscle: smooth, skeletal and cardiac.

29. Levels of Organisation C Organs Organs consist of groups of tissues working together to perform specific functions.

30. Levels of Organisation C Organs eg. the Heart The heart is a muscular organ found in all animals with a circulatory system. It is composed mostly of cardiac muscle and connective tissue, but also nervous tissue and blood.

31. Levels of Organisation D Organ system An organ system is a group of organs that work together to perform a certain task.

32. Levels of Organisation D Organ system eg. the Digestive system The digestive system consists of numerous organs, including the stomach and liver. It digests food and enables it to be absorbed into the blood stream.

33. Levels of Organisation A. Cells B. Tissues C. Organs D Organ system

34. 2.5 identify the chemical elements present in carbohydrates, proteins and lipids (fats and oils) 2.6 describe the structure of carbohydrates, proteins and lipids as large molecules made up from smaller basic units: starch and glycogen from simple sugar; protein from amino acids; lipid from fatty acids and glycerol 2.7 describe the tests for glucose and starch 2.8 understand the role of enzymes as biological catalysts in metabolic reactions 2.9 understand how the functioning of enzymes can be affected by changes in temperature, including changes due to change in active site 2.10 understand how the functioning of enzymes can be affected by changes in active site caused by changes in pH 2.11 describe experiments to investigate how enzyme activity can be affected by changes in temperature. Lesson 1 c) Biological molecules

35. Biological molecules To maintain a healthy body we need to eat the right amount of food and also the right types of food.

36. Biological molecules Our diet needs to contain sufficient and balanced quantities of carbohydrates, proteins and lipids.

37. Biological molecules carbohydrates

38. Biological molecules carbohydrates Carbon C

39. Biological molecules carbohydrates Carbon C Hydrogen H

40. Biological molecules carbohydrates Carbon C Hydrogen H Oxygen O

41. Biological molecules carbohydrates Carbon C Hydrogen H Oxygen O Eg. glucose, C6H12O6

42. Biological molecules carbohydrates

43. Biological molecules carbohydrates

44. Biological molecules carbohydrates

45. Biological molecules Fats Fats also contain C, H and O, but relatively less O. Fats occur in both plant and animal foods. Fats – solid at room temperatures. Oils - liquid at room temperatures.

46. Biological molecules Fats Fats also contain C, H and O, but relatively less O. Fats occur in both plant and animal foods. Fats – solid at room temperatures. Oils - liquid at room temperatures. Fats also give us energy. They also provide insulation in humans and other mammals, and are energy stores.

47. Biological molecules Proteins Proteins contain C, H and O, and also some nitrogen (N) and a little suplhur (S). Proteins are found in milk, eggs, meat and fish.

48. Biological molecules Proteins Proteins contain C, H and O, and also some nitrogen (N) and a little suplhur (S). Proteins are found in milk, eggs, meat and fish. Proteins are needed for growth and body-building (muscles and skin), and they are also used to make enzymes.

49. Biological molecules

50. Biological molecules Simple sugars Starch / glycogen